Old bike - keep or sell? Your opinion?

It would depend on the duration and frequency of my rides. Greater frequency and/or longer duration would have me leaning towards getting the more comfortable carbon bike.

Do you really just want a new toy? If so, get yourself something that you really desire - not your friend's cast-away - so you won't regret your decision later...

maba said:

I have an almost 20 year old bike that was custom made for my measurements. I also went all out and put great components on it (mostly Dura Ace) and the frame is Columbos SPX.
I'm considering selling it and replacing it with a carbon frame bike for the following reasons ("in order of priority"😉: less vibrations, more comfortable ride, 18 or 20 speed instead of 14, weight of the bike.
I have a very good offer for a carbon bike with Shimano 105 equipment from a friend who bought it a couple of years ago. I could probably sell mine for the same price I would pay him. But I'm a bit concerned about fit. It felt ok on a short test ride and I would most likely be ok to adjust it to my needs (worst case scenario replace stem and handlebar).
What would you do? Keep the old perfectly fitting bike, or get the new one?

Carbon fiber frames are nice & 105 components are pretty good, BUT 'I' think you should seriously consider keeping your "perfect fitting bike" and that you should simply update the shifters, rear hub, etc.

So, FWIW, here's the-other-side-of-the-coin ....
[INDENT]MY observation is that the better (?) carbon fiber frames and forks were originally fabricated to simulate the ride of a good steel frame OR fork ...

Almost a decade ago, I changed the pretty-good riding steel fork on my mid-80s Peugeot to a LOOK carbon fiber fork ... the bike was a pound lighter, but the ride didn't change!

My circa 2001 (designed-and-spec'd several years earlier), high zoot carbon fiber frame has the same main triangle geometry as the fore mentioned Peugeot ... the CF bike is much lighter but porky by today's standards ... most signficantly, the ride was not perceptibly different on mountain road descents (both bikes had basically the same components)!

More recently, it seems that the pro riders have requested & received CF frames whose ride may more closely simulate the ride of an alloy frame than a steel frame ...

Regardless, I'm not sure that it can be said that a CF frame will be more comfortable than your steel framed bike.
[/INDENT]If your bike's rear triangle has 130mm spacing, then you can readily upgrade it by simply installing a pair non-QS, 10-speed Campagnolo shifters, changing the rear hub/wheel, the rear derailleur, the chain ...
[INDENT]The 10-speed Campagnolo shifters will index with 8-/9-/10-speed Shimano cassettes with the "right" rear derailleur.

I respaced my mid-80s OLMO [see attachment] from 126mm to 130mm & updated all the components -- the current shifters are 10-speed Campagnolo Centaur (non-QS), the front derailleur is a 9-speed Shimano Ultegra, the rear derailleur is currentlly a 10-speed Shimano 105 with different pulley wheels, the rear cassette is a 9-speed Shimano XT, the chain is a 9-speed Shimano chain ...

Previously, the bike had an XTR rear derailleur with a hubbub'd cable connection & the same 9-speed Shimano cassette ... prior to that, an XT rear derailleur and an 8-speed cassette.

N.B. 7-speed and 8-speed spacing are pretty close. If your current budget is limited then initially you could just get a pair of 10-speed Campagnolo shifters & mate them with the appropriate Shimano rear derailleur ...

Also, the non-QS Campagnolo LEFT shifter will index with ANY front derailleur ...

So, you could probably update your current bike for the cost of a pair of Campagnolo shifters + cable/housing/downtube-stops + new handlebar tape. Non-QS shifters will set you back between $100+ to $400+ ... approximately, the used to new price range ...

The Campagnolo shifters (as with Shimano shifters) are often packaged with the housing, cables & downtube stops.
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